Question

If two brown-eyed sheep that are heterozygous for eye color reproduce, what percentage of their offspring would be expected to have brown eyes?

Answer 1

When two heterozygous brown-eyed sheep mate, we can use a Punnett square to determine the offspring's eye color. The expected phenotypic ratio is 75% brown-eyed offspring due to the presence of either one or two dominant alleles.

Step-by-step explanation:

When two brown-eyed sheep that are heterozygous for eye color mate, we can predict the expected phenotypic ratio of their offspring's eye color using a Punnett square. Heterozygous means that each sheep has one dominant allele for brown eyes (B) and one recessive allele for another eye color (b). The possible genotypes for the offspring are BB (homozygous dominant), Bb (heterozygous), and bb (homozygous recessive).

The BB and Bb genotypes would result in brown eyes, while the bb genotype would result in the recessive eye color. The expected ratio of offspring with brown eyes would therefore be 75%, as the BB and Bb genotypes each occur with a probability of 25% and 50% respectively, adding up to 75% with brown eyes (BB + Bb). The remaining 25% would represent the bb recessive phenotype.

Answer 2

Let's assume that the recessive allele represents a different eye color.

If we put Bb x Bb in a Punnett square, we get 4 possible combinations, BB, Bb, Bb again, and bb. If this is based on complete dominance, then the percentage of the sheep's offspring expected to have brown eyes would be 75% and the percentage expected to have a different eye color would be 25%.